The invention relates to a resolver correction device and a semiconductor device and particularly to a resolver correction device and a semiconductor device used for controlling a motor.
Japanese Unexamined Patent Application Publication No. Hei 8 (1996)-307208 describes that two all path filters (APF: All Pass Filter) having different phase shift amounts are used and designed to shift the phase of one output from the phase of the other output by a predetermined amount, hence to obtain a predetermined shift amount in a wider band width because each shift amount of the signal frequency has the same degree of variation.
Japanese Unexamined Patent Application Publication No. 2002-344310 describes that a phase shift amount is detected and controlled to a predetermined value, hence to obtain a predetermined phase shift amount by using an APF replica as a variable delay circuit.